1. Field of the Invention
This invention relates generally to the mounting and dismounting of tires on a rim, and, more particularly, to an apparatus and method of mounting and dismounting tires on a wheel while the wheel remains attached to a vehicle. This invention also incorporates a method for cutting a tire into more than one part without removing it from a vehicle.
2. Description of Related Art
Tire changers or mounting apparatus are well known. These apparatus normally include a table or supporting surface on which a wheel, with or without a tire, is positioned and clamped, or otherwise secured in place. The wheel is then rotated via a supporting table, by some type of device, such as an electric motor, or the like, in the apparatus. During rotation of the table/wheel, a corresponding stationary tire bead deflecting device is positioned juxtaposed to the rotating wheel, and the tire to be mounted onto or dismounted from the wheel. A great deal of mechanical design and development of these tire machines is attributable to bringing the bead deflecting device into position next to the turning wheel, without actually contacting the wheel itself, to avoid damaging the wheel. This method also requires a large swing arm, which must be strong enough to support the bead-deflecting device during the installation and removal of tires. The swing arm enables the bead-deflecting device to be swung into and out of its working position.
Furthermore, the known method of tire mounting and dismounting also requires a separate bead breaking process step even before a wheel is placed on the rotatable table for the final mounting or dismounting process described above. The breaking of the seal of the tire beads from the flanges of the wheel is accomplished via a shovel plate, which is forced against a side of the tire, while the wheel/tire is held against the side of the tire machine, or other flat surface. Examples of such known tire mounting devices are shown in U.S. Pat. Nos. 3,791,434 to Duquesne, 4,230,170 to Duquesne, 4,606,393 to Cuccolini, 4,896,712 to du Quesne, 4,986,328 to Metzger, and 5,836,368 to Corghi. Both sides of the tire have to have the seals between the tire bead and wheel flange broken. The wheel and tire are then placed on the rotatable table and the process continued, as described above. This is a time consuming process, and an attempt to speed up this process by combining the bead breaking step and tire table rotation process together is disclosed in U.S. Pat. No. 4,986,328 to Metzger. The problem with this technique is that the amount of force needed to break the seal between a tire bead and the wheel flange is often in excess of 2000 lbs. per square inch. The clamping device used to hold the wheel onto the rotatable table is not sufficient for such loads. If the tire is not able to be gently turned, and the seals between the tire beads and wheel flange broken via the disclosed bead-breaking clamps, this system begins to fail because the turntable wheel clamps will not be able to hold the wheel to the table when heavier loads are applied.
All of the known prior art devices in the field of mounting tires on and dismounting tires from wheels require that the wheels be taken off a vehicle, or from storage, and brought to the apparatus. The present invention, which mounts or dismounts a tire while the wheel remains on the vehicle, saves more than half the time, when compared to known methods and apparatus.
Today, the largest area of liability for companies that provide tire installation service is attributed to the unbolting and bolting of wheels to a vehicle. Problems that can arise out of this part of the process are numerous and expensive. For example, a striped lock nut might require jack hammering the lock nut off of a stud that holds the wheel. New studs sometimes have to be replaced before the vehicle can be safely driven again. Bolting the lug nuts back onto the vehicle correctly without over tightening (and causing stripping of the stud), or under tightening (and having the wheel fall off the vehicle while on the road). Many tools are made and sold specifically for the purpose of correctly accomplishing this task of removing and installing a wheel to a vehicle. A common tool for this process is an air impact gun, which generates loud noises. Such air impact guns must meet local code requirements, as to the time of use and type of sound deadening materials used in building in which they can be operated.
Furthermore, tires are expensive to dispose of, and are considered hazardous material due to their shape and volume. Therefore, it is expensive to dispose of whole tires.
At the present time, most old tires are recycled in a process that mulches the tires into tiny bits of rubber. One example of such a process is disclosed in U.S. Pat. No. 5,285,707 to Lodovico. This process produces a "crumb rubber", which is mixed with asphalt for roadways. Also, old tires are being used as fuel in furnaces at cement factories and to generate electricity. However, these uses have not lowered the cost of disposing of old junk tires by tire businesses because: 1. the supply of old tires has always out paced demand for their use; and, 2. The shape and volume of tires cause them to be difficult to handle, store and ship.
U.S. Pat. Nos. 4,012,973 to Tupper, 4,250,940 to Curry, 4,306,607 to Curry, 4,805,507 to Schmidt, 5,133,236 to Dudley and 5,235,888 to Dom all disclose inventions that hold and cut up old tires to change their shape and make the tire non-hazardous, easy to ship, and still useful to the businesses trying to recycle the rubber by-products. However, these machines are expensive to buy, require a lot of space in a tire store and require a further process which tire stores do not have the space and time to perform.
Therefore, there exists a need in the art for a machine that can mount and dismount tires onto wheels without the need for raking the wheels off the vehicle. And, further still there exists a need in the art for a machine which can cut old tires while they are being removed from a wheel, to change their shape and volume to make them easy to handle and less costly to dispose of.